Over the past decade, there has been increased demand for laptop computers, especially in light of their enhanced data processing capabilities. Operating from either external or portable power sources, conventional laptop computers feature a display housing pivotally connected to a body case. Typically, the display housing includes a liquid crystal display (LCD) while the body case includes a keyboard and a secondary input device, such as a roller ball or a touch pad for example.
In order to access the keyboard and view displayed content on the LCD, a user places the body case on a surface (e.g., the user's lap or a fixed surface) and opens the computer by pivoting the display housing away from the body case. As a result, the user is able to access the keyboard and secondary input device as well as to read the displayed content. Similarly, to close the computer after use, the user pivots the display housing toward the body case and secures the display housing thereto.
Recently, due to the growing popularity of personal digital assistants, laptop computers have been configured to alternatively operate as a tablet computer, with a stylus pen operating as the input device. This requires the display housing to be inverted, namely the LCD is positioned to be viewable and resting against the body case. The inverting and pivoting of the display housing has been previously accomplished by a shaft attached to a bottom portion of the display housing. The shaft provides a vertical center axis to allow the display housing to be rotated horizontally 180 degrees about this center axis before it is rotated vertically in a downward direction toward the user. This structure, however, possesses a number of disadvantages.
For instance, one disadvantage is that a substantial amount of force is exerted on the shaft which, over prolonged use, may cause the shaft to break prematurely. Another disadvantage is that the shaft merely provides a single point of contact, which tends to provide an unacceptable amount of instability for the display during adjustment and normal usage. Yet another disadvantage is that a brake hinge may be adapted to a rear surface of the display housing. Thus, the thickness of the electronic device cannot be reduced beyond the sizing of the hinge mechanism itself.